The present invention relates generally to lighting devices such as light emitting diode (LED) drivers. More particularly, an embodiment of an invention as disclosed herein relates to an electrically isolated method for digitally dimming, configuring and updating the firmware of a programmable lighting device through wireless communication.
Lighting devices such as light emitting diode (LED) drivers frequently have their operating parameters configured before shipping to customers for installation. Various operating parameters of the LED driver are typically re-configured at other stages of application, as for example when a driver is first removed from its packaging it may be desired to apply a default configuration to satisfy the needs for most of the LED drivers at a particular installation. Further, once a new driver is installed with other LED drivers in a luminaire, it may be required that all the drivers in the luminaire or series of luminaires receive a configuration unique to their installation.
It would be desirable to provide one convenient device that is capable of configuring drivers without application of AC mains input power to the LED driver, and is also capable of reprogramming LED drivers without the need for a constant wired (e.g., USB) connection. It would be further desirable for the device to be easily implemented and even capable of being connected to the LED driver (or to the luminaire in functional association with the LED driver) with one hand.
There are numerous examples of methods to program and/or reprogram microcontrollers, using for example dedicated programming connections or a bootloader. There are also examples of handheld devices and methods developed to configure certain LED drivers by implementing near field communications (NFC) technology. However, there are no known arrangements that can both configure and reprogram an NFC equipped LED driver.
To program or reprogram the microcontroller of an LED driver, there are numerous examples of commercial programming devices, some of which can be powered by an external battery for remote operation. Another common option for programming and reprogramming is to install a bootloader in the microcontroller to facilitate the programming via a nonproprietary interface, examples of which may include a synchronous serial interface, such as an SPI or I2C interface, or an asynchronous serial interface, such as a UART interface.
It is common for an LED driver to be equipped with NFC technology to provide a means for operation configuration without having an AC mains input applied to the LED driver. An NFC reader/writer may be placed in the non-volatile memory of the NFC equipped driver that represents a change in LED driver behaviors or operable levels.
Typical NFC reader/writers require an external power source, via for example a USB connection to a personal computer (PC) or laptop, which can be convenient if the LED driver has not already been installed in a luminaire. An example of where this method can be convenient is within a pre-assembly area of a luminaire manufacturer where a PC or laptop and an NFC reader/writer is provided. The NFC equipped drivers are removed from the provided transportation housing, the antennae are moved one at a time within proximity of the NFC reader/writer's antenna, and configuration data is placed in the non-volatile memory of the respective driver.
Energy and data are transferred by magnetic flux lines generated by the reader/writer, which are absorbed into the sheet steel commonly used by luminaires and LED drivers, making this process inconvenient at best after the LED driver is installed in a luminaire.
Furthermore, once the luminaire with the NFC equipped driver is installed at a job site, the length of the USB cable connecting the NFC reader/writer to the PC or laptop and the complication associated with attempting to manage a PC or laptop while simultaneously attempting to reach an installed luminaire make this method even more inconvenient and difficult. For example, if a luminaire is installed in a ceiling with an NFC equipped LED driver that requires reconfiguration, an installer would likely have to climb a ladder with a laptop and a USB connected reader/writer and attempt to reconfigure the driver via NFC, the inconvenience and potential dangers of which may be readily appreciated.